CN1032499C - Perfusion pile under-reaming press head and reaming method - Google Patents
Perfusion pile under-reaming press head and reaming method Download PDFInfo
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- CN1032499C CN1032499C CN 92105256 CN92105256A CN1032499C CN 1032499 C CN1032499 C CN 1032499C CN 92105256 CN92105256 CN 92105256 CN 92105256 A CN92105256 A CN 92105256A CN 1032499 C CN1032499 C CN 1032499C
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Abstract
The present invention relates to a perfusion pile reaming press head and a reaming method thereof. A vertical shaft is connected with a multi-stage oil cylinder. A loading equalizer is arranged outside the vertical shaft. A return oil cylinder is arranged on the upper part of an inner cavity of the vertical shaft. A piston rod is connected with a steel cable which is connected with a pile die by four guide wheels. The pile die is connected with an upper top plate by a hinge of an upper torsion spring, and is connected with a clean-up scraper by a hinge of a lower torsion spring. A guide plate is fixed outside the middle part of the pile die by bolts. A positioning head is connected to the lower side of the oil cylinder. A horizontal rule is also hinged at the middle part of the pile die, and can slide in a slide way on the oil cylinder. A spacing contact point is arranged at the left end of the horizontal rule. A limit switch is arranged on the oil cylinder. The perfusion pile reaming press head is mainly used for reaming a pile hole. The multi-stage oil cylinder is used for extruding towards both sides of a pile. Thus, collapse is avoided, bottom soil is cleaned cleanly, the shape of a pile hole is correct, and the strength of the pile hole is increased.
Description
The present invention relates to a kind of castinplace pile reaming pressure head and expanding method, be mainly used in the base diameter that enlarges priming concrete pile hole, increase the contact area of castinplace pile bottom and ground, to improve the supporting capacity and the resistance to plucking ability of stake.This invention belongs to the technical field of pile hole construction device.
At present in building trade, the castinplace pile that departments such as power industry adopt usually bores reaming construction method and equipment mainly is divided three classes, the first kind is to hold with both hands with both hands under the artificially to dig reaming, efficiency of construction is low, labour intensity is big, can not adapt to the needs of construction, especially holds with both hands with both hands to dig the landslide accident takes place often, reach personal injury, so construction department has expressly provided and stops to use.Second class is that barrel shape bores an expansion mechanical hole reaming, for example Chinese patent 85205107 and US patent 3513920 are introduced, its reaming bit is mainly by boring bucket, cornish bit and transmission mechanism are formed, its principle is the soil body that cornish bit downcuts to be pushed bore in the bucket, fill after one barrel, just mention casting on the ground, through repeated operation, just can finish the reaming action, because transmission mechanism is contained in the bucket, shared space is bigger, and bad the causing of soil-shifting effect of cutting the ejector dozer the cutter of hole under store soil seldom in the bucket, finishing of reaming work needs repetitive operation to carry 12～20 barrels in soil up and down, its major defect be bore bucket repeatedly up and down operation can collide hole wall, bigger vibration takes place, hole wall is produced caves in; The surplus soil of bottom, stake hole also is difficult to remove clean, influences the pile foundation load-carrying properties, and the time of ream forming is longer, inefficiency, and the chance that underground water is infiltrated in the hole increases, and the adaptive capacity of geological conditions is also poor.The third is to adopt double helix to bore to expand head, for example 2K-3 type hydraulic walking drilling reamer and YZK-100 type hydraulic pressure drilling reamer, and the existing rotation of double helix drill bit has mutual revolution again.Utilize the end to cut native cutter and finish boring.The double helix Lower Half can be separated to both sides by universal coupling, cuts soil by both sides and finishes reaming.The both goes up casting earthward by double helix.Its shortcoming is a complex structure, and power requirement is bigger, and efficient is low, and soil discharge channel is comparatively narrow, is stopped up by rubble easily, and is relatively poor for the adaptive capacity of geological conditions, and the surplus soil of bottom, post hole does not clean up the supporting capacity that yet influences pile foundation.These three kinds of methods all are to manage the soil in the enlarged footing part at the bottom of the hole got on the ground to get rid of, and always can produce above-mentioned various shortcoming.
Purpose of the present invention will provide a kind of castinplace pile reaming pressure head, it can overcome above-mentioned shortcoming, make the hole wall after the reaming smooth, intensity increases, especially effectively the surplus soil that stores at the bottom of preventing hole wall landslide and guaranteeing cleaning hole neatly improves speed of fulfiling hole and significantly to the adaptive capacity of various soil properties.
Another object of the present invention is that a kind of new castinplace pile chambering process method will be provided, and it can be increased work efficiency, and prevents the landslide accident, thoroughly surplus soil at the bottom of the cleaning eye.
Another object of the present invention is that a kind of process and reaming pressure head will be provided, and it can realize that a hole becomes the construction of Pear-Shaped.
The object of the present invention is achieved like this, vertical shaft at pressure head is connected with the single-acting multi-stage oil cylinder, the return oil cylinder is housed in the vertical shaft inner chamber, 4 wire rope of the terminal connection of its piston masthead, stride across 4 return directive wheels and be connected with the stake mould, stake mould top is hinged with torsion spring hinge and upper plate, and the also following torsion spring hinge in bottom connects a clean-up scraper, but surplus soil at the bottom of the cleaning hole.Slideway and travel switch are housed on the multi-stage oil cylinder, the hinged scale in stake mould middle part, the scale end is equipped with spacing contact, scale is slippage in slideway, when stake hole companding to preliminary dimension, spacing contact and travel switch collide, so companding action termination, hydraulic oil enters the return oil cylinder, make piston rod pulling wire rope and make a mould be withdrawn into the home position, angle of rotation stake mould is proceeded companding again, after so continuous rotation 4～8 times, but just companding becomes a complete truncated cone-shaped stake hole.Positioning head is equipped with in the oil cylinder bottom, guarantees that pressure head can deflection, and in addition, there is the load balancing device vertical shaft outside, guarantees its positioning action, prevents the hole wall landslide, and a guide strip is fixed with screw in the outside, stake mould middle part, can guarantee the unlikely deflection of companding direction.
The schematic diagram of Fig. 1 castinplace pile reaming pressure head
The vertical view (A-A analyses and observe) of Fig. 2 castinplace pile reaming pressure head
The schematic diagram of Fig. 3 positioning head
The upward view of Fig. 4 positioning head
The schematic diagram of Fig. 5 scale device
Fig. 6 wire rope connection diagram
The schematic diagram of Fig. 7 Bottle gourd pile
Now in conjunction with the accompanying drawings the structure of castinplace pile reaming pressure head is described in further detail.
Fig. 1 is the schematic diagram of castinplace pile reaming pressure head, the vertical shaft of erectting (1) is connected with two flexible single-acting multi-stage oil cylinders (5), return oil cylinder (2) is equipped with on the inner chamber top of vertical shaft (1), the top of its piston rod (15) is connected with the 4 rotation wire rope (9) that all around are symmetrically distributed, wire rope (9) strides across 4 return directive wheels (4) of symmetry all around, be connected with two platform shape stake moulds (8) symmetrically respectively again, stake mould (8) upper end is connected with upper plate (6) again by last torsion spring hinge (7), its middle part is connected with the stroke scale (10) of horizontal positioned again, scale (10) can slippage in scale slideway (11), and its left end is provided with and can goes up the spacing contact (13) that changes the permanent position at scale (10).Load equalizer (3) is equipped with in vertical shaft (1) outside, and its external diameter is slightly less than a hole internal diameter, and both gaps play the effect of location at 3～10 millimeters, makes two flexible single-acting multi-stage oil cylinder (5) vertical shafts (1) can deflection, prevents the landslide of hole wall.Positioning head (14) is equipped with in two flexible single-acting multi-stage oil cylinders (5) below, also make two flexible single-acting multi-stage oil cylinders (5) and vertical shaft (1) keep the tram, two flexible single-acting multi-stage oil cylinders (5) both sides respectively are provided with one stroke switch (12), when stake mould (8) both sides expansion to the left and right moves on to extreme position, contact (13) impact stroke switch (12) makes oil cylinder (5) stop action.
In order to improve bi-directional expansion, single-acting multi-stage oil cylinder (5) is to the adaptive capacity of various soil property earth bearing strengths, its rated pressure can be aligned between 15～32MPa, the thinnest final stage piston diameter must be defined as 150～250mm, piston rod materials at different levels can be selected 27SiMn for use, 30CrMo, structural alloy steels such as 35CrMo or 38CrMoALA.
In order to increase the total kilometres of bi-directional expansion single-acting multi-stage oil cylinder (5), with the reduction cost, the logical oily structure of piston rods at different levels all is single-acting structures, mainly relies on the inner hydraulic oil that feeds of oil cylinder, piston rods at different levels are stretched out outside the cylinder, rely on external force to make it retract to the origin-location.
In order to make bi-directional expansion single-acting multi-stage oil cylinder (5) at extruding stress equalization during hole wall, both sides are flexible to the left and right simultaneously must to make pistons at different levels, at this moment also rely on the positioning head (14) that is arranged on the load equalizer (3) on top and is arranged on the bottom to play a supporting role.
When platform shape stake mould pushes hole wall to both sides, the structure that torsion spring hinge (7) is connected with upper plate (6) in the employing.Can increase the top soil area of platform shape stake mould (8) upper edge, the scope of activities of upper plate (6) can only be in Fig. 1 changes in the represented position of solid line and dotted line.Platform shape stake mould (8) bottom also uses a following torsion spring hinge (16) to connect a clean-up scraper (17), also dotted line position in the drawings during beginning.Just reach position shown in the solid line at last, it mainly acts on is to clear up a surplus soil of bottom, hole when extruding.
Its piston rod of return oil cylinder (2) (15) that is contained in the vertical shaft (1) joins with wire rope (9), is connected in a mould (8) by directive wheel (4), and its effect can make a mould (8) and multi-level piston bar all turn back to the origin-location.
Fig. 2 be accompanying drawing 1 vertical view (A-A analyses and observe) wire rope (9) by 4 directive wheels (4) respectively with about 2 platform shape stake moulds (8) be connected, the multi-level piston of two flexible single-acting multi-stage oil cylinders (5) is terminal to be connected with platform shape stake mould (8) middle part, each uses bolt (19) fixedly connected guide strips (20) outside, platform shape stake mould (8) middle part, guide strip (20) length is about 200～400 millimeters, and width is 30～150 millimeters.It can make a mould when the soil of top, keeps demarcating among Fig. 2 correct direction.
When reaming extruding soil, the necessary while of its multi-level piston of bi-directional expansion single-acting multi-stage oil cylinder (5) (15) is soil compaction round about, at first press 1-1 line direction reaming soil compaction during the extruding hole wall, make a mould half-twist then, for the second time again by 2-2 line direction reaming soil compactions, be by 3-3 line direction reaming soil compactions for the third time, follow 4-4 lines, 5-5,6-6,7-7,8-8 line soil compactions, angle 22.5 degree (five equilibrium) can fully guarantee efficiency of construction like this between every line, quality with reaming, deflection takes place when preventing to push up soil, for aperture hour when 2000mm (for example aperture＜), generally as long as 4 reaming soil compactions just can be finished reaming.
The schematic diagram of Fig. 3 positioning head, positioning head (14) top is connected with a taper partly (26), be connected in above two flexible single-acting multi-stage oil cylinders (5) with bolt (24) by a flange (25) again, positioning head (14) can play positioning action in bottom, stake hole, can prevent under uneven external force effect simultaneously, the piston rods at different levels of two flexible single-acting multi-stage oil cylinders (5) are rotated in its outer cylinder, cause platform shape stake bore deformation.
The upward view of Fig. 4 positioning head, positioning head (14) are by 4 plate butt joints, are combined into cross shape, and the length of every block of plate is 80～160 millimeters, and wide is 60～140 millimeters, and the blade of cusped edge (27) is arranged at the bottom of plate.(Fig. 3)
The schematic diagram of Fig. 5 scale device, when the left end of scale (10) is connected with a spacing contact (13) with travel switch (12) collision, two flexible single-acting multi-stage oil cylinders (5) can stop top soil, scale (10) right-hand member is to compress spring (21) and stretch in the scale sleeve pipe (22) at ordinary times, scale sleeve pipe (22) can slippage in slideway (11) together with scale (10), scale sleeve pipe (22) right-hand member is hinged with stake mould (8) middle part, the left part of two flexible single-acting multi-stage oil cylinders (5) is equipped with block (23), scale (10) is when being moved to the left, can touch block (23), be compressed and enter in the scale sleeve pipe (22).
Fig. 6 is the connection diagram of wire rope
The piston rod (15) of return oil cylinder (2) has a cap head (28), and wire rope strides across 4 fairleads (18), and rivets tightly on cap head (28).
The companding size range of castinplace pile pressure head is:
Unit: millimeter
| The straight hole diameter | Counter bore diameter | ||||||
| First series | 1200—1000 | 3200 | 3000 | 2800 | 2600 | 2400 | 2200 |
| Second series | 800-700 | 2600 | 2400 | 2200 | 2000 | 1800 | 1600 |
| The 3rd series | 600—500 | 2000 | 1800 | 1700 | 1600 | 1500 | 1400 |
| The Quaternary system row | 400—300 | 1500 | 1400 | 1300 | 1200 | 1100 | 1000 |
The process of castinplace pile reaming:
During the hole for grout pile construction, the short augers that adopts usually with construction sector bores dark 15 meters of straight hole earlier, and 800 millimeters of aperture φ propose this drill bit then.Castinplace pile reaming pressure head of the present invention is linked to each other with rig power source by vertical shaft (1), placing the bottom of having holed under the pressure head, feed hydraulic oil to two flexible single-acting multi-stage oil cylinders (5), make the multi-level piston bar on both sides promote platform shape stake mould (8) to both sides extruding hole wall, upper plate (6) is subjected under the hole wall barrier effect, turn to solid line position by dotted line position among Fig. 1, push hole wall simultaneously with platform shape stake mould (8), when the reaming size reaches given size numerical value, spacing contact (13) impact stroke switch (12) on the stroke scale (10) is so extruding reaming action just stops to carry out.In the companding process before collision, platform shape stake mould (8) is the piston rod (15) that drives return oil cylinder (2) by shackle line (9), makes it and two flexible single-acting multi-stage oil cylinders (5) and multi-level piston be drawn out the cylinder body outside synchronously when stretching out.Put in place the collision after, in return oil cylinder (2), feed hydraulic oil again, make its piston rod (15) retract to the origin-location again, and also be withdrawn into the origin-location synchronously by rotating the multi-level piston bar that wire rope (9) drives platform shape stake mould (8) and pair flexible single-acting multi-stage oil cylinders (5), at this moment hole wall is fallen the part of full circle by companding, presses among Fig. 2, pressure head is rotated to an angle, repeat above-mentioned action again, through repeatedly action, till the full circle of hole wall part is all by companding.
Adopt above-mentioned process also can carry out the brill reaming construction (accompanying drawing 7) of Bottle gourd pile, at first be drilled to the identical straight hole of diameter, be taken up in order of priority two or more truncated cone-shaped pile crowns of companding then, Bottle gourd pile strengthens the pressure-bearing and the extraction-resistant behavior of pile foundation significantly.
Compared with prior art, the bored concrete pile reaming pressure head has following advantages:
1, utilizes the characteristics that hydraulic jack is exerted oneself greatly, structure is little, can obviously reduce output power of power source.
2, with the soil of stake hole enlarged footing part companding towards periphery, reaming hole wall intensity is obviously increased, the hole and slow down ground water seepage speed of can preventing from collapsing, raising equipment is to the adaptive capacity of various soil property operating modes.
3, adopt to press nurse's skill can obviously reduce remaining soil at the bottom of the hole, hole wall is smooth complete, improves the bearing capacity of pile foundation.
Claims (8)
1, a kind of castinplace pile reaming pressure head, it is characterized in that erectting vertical shaft (1) is connected with multistage two flexible single-acting multi-stage oil cylinders (5), return oil cylinder (2) is equipped with on vertical shaft (1) inner chamber top, its piston rod (15) top is connected with shackle line (9), be connected with platform shape stake mould (8) by return directive wheel (4), platform shape post mould (8) upper end is connected with upper plate (6) again by last torsion spring hinge (7), platform shape stake mould (8) middle part links to each other with scale (10), scale (10) slippage in slideway (11), scale (10) left end has spacing contact (13); Load equalizer (3) is equipped with in vertical shaft (1) outside, two flexible single-acting multi-stage oil cylinders (5), and there is positioning head (14) below, and limitation travel switch (12) is equipped with in its both sides, the hinged clean-up scraper of the following again spring hinge in platform shape post mould (8) bottom (16) (17).
2, reaming pressure head according to claim 1, it is characterized in that positioning head (14) is by 4 plate butt joints, be combined into cross shape, its top is connected with a reverse taper portion, is connected on two flexible single-acting multi-stage oil cylinders (5) with bolt (24) by flange (25) again.
3, reaming pressure head according to claim 1, it is characterized in that scale (10) right-hand member is compressing spring (21), can stretch in the sleeve pipe (22), scale sleeve pipe (22) is together with scale (10) slippage in slideway (11), sleeve pipe (22) right-hand member and platform shape stake mould (8) middle part are hinged, and two flexible single-acting multi-stage oil cylinders (5) left part is equipped with block (23).
4, reaming pressure head according to claim 1 is characterized in that: be provided with guide strip (20) in the outside, platform shape stake mould (8) middle part, its length is 200～400 millimeters, and width is 30～150 millimeters, is connected on the platform shape stake mould (8) with bolt (19).
5, reaming pressure head according to claim 1, the use rated pressure that it is characterized in that two flexible single-acting multi-stage oil cylinders (5) is between 15～32MPa, the thinnest final stage piston diameter must be defined as 150～250mm, piston materials at different levels can be selected 27SiMn for use, 30CrMo or 38CrMoALA structural alloy steel.
6, reaming pressure head according to claim 1 is characterized in that the external diameter of load equalizer (3) and the gap between the internal diameter of stake hole are 3～10 millimeters.
7, a kind of expanding method of castinplace pile reaming pressure head, it is characterized in that using earlier the auger bit bore, about 1200 to 300 millimeters of aperture, in 15 meters of the hole depths, take out drill bit, at the bottom of then reaming pressure head being placed in the hole, make hydraulic oil feed two flexible single-acting multi-stage oil cylinders (5), so platform shape stake mould (8) is to both sides firming reaming, upper plate (6) moves to solid line position by the dotted line position of Fig. 1 under hole wall stops, can with platform shape stake mould (8) firming reaming simultaneously, when reaming reached certain size, the spacing contact (13) of stroke scale (10) was with regard to impact stroke switch (12), so the reaming action just stops, enter return oil cylinder (2) by hydraulic oil, make piston rod pulling wire rope (9) and platform shape stake mould (8) is resetted, and then a mould is rotated to an angle, continue above-mentioned course of action, continuous like this 4 to 8 times, just can become truncated cone-shaped stake hole to stake hole companding.
8, expanding method according to claim 7 is characterized in that the both sides piston rods at different levels of two flexible single-acting multi-stage oil cylinders (5) must be simultaneously to the both sides expanding-contracting action.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN 92105256 CN1032499C (en) | 1992-07-01 | 1992-07-01 | Perfusion pile under-reaming press head and reaming method |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN 92105256 CN1032499C (en) | 1992-07-01 | 1992-07-01 | Perfusion pile under-reaming press head and reaming method |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| CN1080686A CN1080686A (en) | 1994-01-12 |
| CN1032499C true CN1032499C (en) | 1996-08-07 |
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Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN 92105256 Expired - Fee Related CN1032499C (en) | 1992-07-01 | 1992-07-01 | Perfusion pile under-reaming press head and reaming method |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN1032499C (en) |
Families Citing this family (11)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN1057363C (en) * | 1998-07-10 | 2000-10-11 | 贺德新 | All-intelligent multifunctional hydraulic extruding extender |
| CN100427688C (en) * | 2005-06-09 | 2008-10-22 | 清华大学 | Side downhole soil-extruded foundation treating method and horizontal extruding-spreading device |
| CN102454365B (en) * | 2010-10-18 | 2014-09-24 | 中冶交通工程技术有限公司 | Drilling bit for forming branches of branch pile |
| CN104625900B (en) * | 2013-06-16 | 2017-01-18 | 杨昌松 | Drill bit and drilling method |
| CN103419285B (en) * | 2013-08-01 | 2015-04-08 | 鲍林富 | Processing method of hollow stone container |
| CN103615197B (en) * | 2013-11-30 | 2015-06-17 | 国家电网公司 | Excavation foundation bottom end reaming device |
| CN108252297B (en) * | 2018-01-19 | 2019-11-12 | 河海大学 | A kind of anchor thorn bored concrete pile and its construction method |
| CN108222837A (en) * | 2018-01-19 | 2018-06-29 | 中冶交通建设集团有限公司 | Rotary excavating extruding expanding drilling head, the rotary drilling rig and construction method for including it |
| CN109930993A (en) * | 2019-04-22 | 2019-06-25 | 北京城建勘测设计研究院有限责任公司 | A kind of pebble layer tube well dewatering well formation device and construction method |
| CN110043187B (en) * | 2019-05-16 | 2024-01-30 | 北京中岩大地科技股份有限公司 | Hydraulic diameter-variable reaming bit of long spiral drilling machine and construction method of cast-in-place pile |
| CN110258565B (en) * | 2019-06-18 | 2020-10-09 | 重庆交通大学 | Foundation pile hole bottom deslagging device and deslagging method |
-
1992
- 1992-07-01 CN CN 92105256 patent/CN1032499C/en not_active Expired - Fee Related
Also Published As
| Publication number | Publication date |
|---|---|
| CN1080686A (en) | 1994-01-12 |
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